The aim of this project is to enhance food security for resource-poor rural people in Eastern Africa through research that underpins national programmes to scale up the use of trees within farming systems in Ethiopia and Rwanda and then scale out successes to relevant agro-ecological zones in Uganda and Burundi. The specific objectives of the project are: To characterize target farming landscapes and systems, and develop tools for matching species and management options to sites and circumstances. To generalize predictions of impacts of tree species and management on crop productivity, water resources and nutrients at field, farm and landscape scales to inform scaling up to improve food security and reduce climate risk. To develop effective methods and enabling environments for scaling up and out the adoption of trees on farms. To develop databases and tools for monitoring and evaluation of the impact of scaling up and out the adoption of trees on farms. To enhance capacity and connectivity of national partner institutions (including farmer groups) in developing and promoting locally appropriate options for adoption of farm trees.